MDB: Set minimum value constraint for MinAvailable and MaxUnavailable

[ingvagabund]

After applying the change and applying:

apiVersion: healthchecking.openshift.io/v1alpha1
kind: MachineDisruptionBudget
metadata:
  name: mdb-test
  namespace: kubemark-provider
spec:
  selector:
    matchLabels:
      machine.openshift.io/cluster-api-cluster: kubemark
      sigs.k8s.io/cluster-api-machineset: kubemark-scale-group-2a
  maxUnavailable: -2

I get:

The MachineDisruptionBudget "mdb-test" is invalid: []: Invalid value: map[string]interface {}{"apiVersion":"healthchecking.openshift.io/v1alpha1", "kind":"MachineDisruptionBudget", "metadata":map[string]interface {}{"annotations":map[string]interface {}{"kubectl.kubernetes.io/last-applied-configuration":"{\"apiVersion\":\"healthchecking.openshift.io/v1alpha1\",\"kind\":\"MachineDisruptionBudget\",\"metadata\":{\"annotations\":{},\"name\":\"mdb-test\",\"namespace\":\"kubemark-provider\"},\"spec\":{\"maxUnavailable\":-2,\"selector\":{\"matchLabels\":{\"machine.openshift.io/cluster-api-cluster\":\"kubemark\",\"sigs.k8s.io/cluster-api-machineset\":\"kubemark-scale-group-2a\"}}}}\n"}, "generation":1, "uid":"f2bab200-b1f5-11e9-9a34-bcf37e375394", "name":"mdb-test", "namespace":"kubemark-provider", "creationTimestamp":"2019-07-29T11:42:30Z"}, "spec":map[string]interface {}{"maxUnavailable":-2, "selector":map[string]interface {}{"matchLabels":map[string]interface {}{"machine.openshift.io/cluster-api-cluster":"kubemark", "sigs.k8s.io/cluster-api-machineset":"kubemark-scale-group-2a"}}}}: validation failure list:
spec.maxUnavailable in body should be greater than or equal to 0

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1733473

[spangenberg]

/lgtm
/approve

[openshift-ci-robot]

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